Allegro MicroSystems A1304ELHLT-T

Overview

A1304ELHLT-T from Allegro MicroSystems is a linear Hall-effect sensor IC designed for medium-accuracy position and proximity sensing in space-constrained applications. It delivers ratiometric analog output proportional to magnetic field strength, features 4.0 mV/G sensitivity, operates from 3.3 V supply, and maintains ±40 mV quiescent voltage drift over –40°C to 85°C ambient range - deployed in automotive throttle position feedback and industrial motor commutation.

For engineers reviewing the A1304ELHLT-T datasheet, A1304ELHLT-T pinout, A1304ELHLT-T application, or A1304ELHLT-T equivalent, this page provides verified package mapping (SOT-23W LH), confirmed electrical behavior (ratiometric QVO at 1.65 V, 20 kHz bandwidth), thermal performance (RθJA = 110°C/W on 2-layer PCB), and real-world substitution guidance for linear Hall sensing designs.

Technical Context

The A1304ELHLT-T integrates a BiCMOS monolithic circuit with dynamic offset cancellation via high-frequency chopper stabilization, eliminating thermal and mechanical stress-induced drift. Its internal architecture includes a Hall element, trimmed amplifier, tuned low-pass filter, and proprietary offset correction logic - enabling precise recoverability after temperature cycling and stable operation without external calibration.

This device implements undervoltage lockout (UVLO) with hysteresis, ensuring VOUT remains grounded until VCC exceeds the rising threshold (~2.6 V), then delivering ratiometric output across 3.0–3.6 V supply range. Power-on time is specified at 50–70 µs with 10 nF load, supporting fast-response closed-loop control systems.

Key Specifications

Pinout & Package

The A1304ELHLT-T is housed in a lead-free, 3-pin SOT-23W surface-mount package (Allegro package code LH), featuring 100% matte tin plating and optimized thermal performance (RθJA = 110°C/W on 2-layer PCB).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar linear Hall sensing applications.

Compared with A1304ELHLT-T, the MLX90242 offers higher supply flexibility but requires PCB redesign due to SOIC-8 footprint, while the AH3503-PG1 lacks dynamic offset cancellation - resulting in greater QVO drift and reduced repeatability after thermal stress.

Availability

A1304ELHLT-T is available at Aetrix Electronics and suitable for automotive throttle position sensing, industrial BLDC motor commutation, and medical infusion pump flow verification requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for A1304ELHLT-T includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Allegro MicroSystems is a U.S.-based semiconductor company specializing in magnetic sensing and power ICs, headquartered in Manchester, NH, with global design and manufacturing operations.

The A1304 product line targets cost-sensitive, space-constrained linear Hall applications requiring medium accuracy, thermal stability, and analog output - specifically engineered for automotive subsystems and industrial motion control where ratiometric operation and chopper-stabilized drift rejection are essential.

FAQ

What is the supply voltage range for the A1304ELHLT-T?

The A1304ELHLT-T operates from 3.0 V to 3.6 V, with undervoltage lockout (UVLO) disabling output below ~2.6 V. This ensures reliable operation on standard 3.3 V rails while preventing erratic behavior during brown-out conditions. The A1304ELHLT-T's ratiometric design means its quiescent output and sensitivity scale linearly with VCC across this range, maintaining measurement accuracy without external regulation.

How does the A1304ELHLT-T achieve temperature stability?

The A1304ELHLT-T achieves temperature stability through integrated dynamic offset cancellation using a high-frequency chopper stabilization technique. This BiCMOS-based architecture modulates the Hall signal to separate magnetic response from thermal offset in the frequency domain, then demodulates and filters to recover clean analog output. As a result, the A1304ELHLT-T exhibits only ±40 mV quiescent voltage drift from –40°C to 85°C and ±2% sensitivity hysteresis after thermal cycling.

What is the magnetic field range supported by the A1304ELHLT-T?

The A1304ELHLT-T supports a magnetic field range of ±375 G, derived from its 4.0 mV/G sensitivity and saturation limits (VSAT(HIGH) = 2.87 V, VSAT(LOW) = 0.38 V at 3.3 V supply). This range accommodates typical air-gap configurations in throttle position sensors and BLDC rotor position detection. The A1304ELHLT-T's linearity error is specified at ±1.5% across this full range, ensuring consistent analog response without external compensation.

Can the A1304ELHLT-T be used with a 5 V supply?

No, the A1304ELHLT-T is not rated for 5 V operation. Its absolute maximum forward supply voltage is 5.5 V, but the recommended operating range is strictly 3.0–3.6 V. Supplying 5 V risks exceeding internal voltage tolerances and may cause permanent damage or parametric shift. For 5 V systems, consider alternatives like the Melexis MLX90242, which is explicitly designed for 4.5–5.5 V operation and shares functional similarity with the A1304ELHLT-T.

What bypass capacitor value is required for stable operation of the A1304ELHLT-T?

A minimum 0.1 µF ceramic capacitor must be placed between VCC and GND, as close as possible to the A1304ELHLT-T's pins. This capacitor suppresses high-frequency noise and stabilizes the internal regulator during chopper switching events. The A1304ELHLT-T's electrical characteristics - including noise performance (13 mV_p–p) and power-on time (50–70 µs) - are validated with this value; reducing it degrades noise immunity and may cause startup instability.